This page contains information on how to get syntax highlighting and function list support in Notepad++.

Syntax Highlighting

To add syntax highlighting support copy the UserLang node for Cobra from the userDefinedLanguage.xml file attached below.

Place this XML node in the userDefinedLang.xml file at

%appdata%\Notepad++\userDefineLang.xml

If this file does not exist then copy the entire file to the destination directory.

Note that the colors used are more geared towards themes with a darker background (the majority of them). This is so because the way user defined languages are handled at the moment is by explicitly setting the colors and not a class name. These colors might make it a bit hard to comfortably read text with the default theme, which has a background color of white.
To change your theme go to Settings >> Style Configurator.

For colors more suited to the default theme use the UserLang node for Cobra in the file userDefineLang-DefaultTheme.xml attached below.
Once again if the file userDefineLang.xml does not exist copy the entire file (userDefineLang-DefaultTheme.xml) and rename it to userDefineLang.xml.

Version 6.2 and Post

Notepad++ changed its Language for defining User Languages ( UDL1.0 -> UDL2.0) requiring a slightly different syntax file.
Unfortunately the new UDL doesnt support folding on indent ( which the python lexer does).

So the options now (pending that support in the UDL parser) are:
If you want code folding in cobra - you need to augment the Python description with the additional cobra keywords

Get the Style Config dialog up by selecting Settings >> Style Configurator,
Select 'Python' in the 'Language' List and select 'KEYWORDS' in the Style list